Last updated: 2026-11-03
A private label solar charger is specified by five items: the device it must charge, panel watts, USB output, battery capacity in Wh or none, and the branding scope. In the worked example below (assumed inputs), a 10 W panel yields about 35 Wh at 5 peak sun hours, roughly two charges of a 15 Wh phone.
A brand owner asked to launch a private label solar charger usually starts with a logo and a retail target, then finds that no supplier can quote until the unit is specified. The supplier needs to know what the unit must charge, how many watts the panel carries and whether a battery sits inside. The checklist, spec comparison and worked sizing below make the first request for quotation complete.
Buying checklist: requirements to confirm
Six requirements need written answers before a private label solar charger goes out for quotation: the target device, the power rating, the battery decision, the ports and cable, the branding scope and the evidence you will accept.
A private label solar charger is a solar charging product built by a supplier and sold under the buyer's brand, usually starting from an existing design with changes limited to branding, packaging and a few specification choices.
Start with the target device. A phone battery of about 15 Wh sets the energy the unit must deliver each day (a typical range is 11 to 19 Wh), while a handheld GPS unit or a headlamp needs far less. Write the device list and the daily energy goal as numbers.
Next, fix the power rating and the port. State the panel wattage, the connector type (USB-A, USB-C or both) and the output voltage and current, for example 5 V at 2 A, which is 10 W at the port. If the unit holds a battery, give its capacity in Wh, because a mAh figure hides the cell voltage.
Then set the branding scope and the evidence. Branding covers the logo position and print method, the retail box, the manual and the barcode label, while evidence is whatever the supplier agrees to provide, such as an output reading under a stated light level or a drawing sign-off.
Certification and transport paperwork depend on the destination market and on whether a lithium battery is inside, so ask a test lab and your freight forwarder which documents apply. For a broader view of portable charger specifications, read the portable solar charger spec guide.
Comparison: options by spec and use case
Private label solar chargers come in three common formats, and they differ in panel watts, battery capacity and the daily job they suit.
| Format | Typical panel rating | Typical battery | Suits | Main spec risk |
|---|---|---|---|---|
| Foldable panel, USB output, no battery | 5 W to 30 W | None | Daytime phone, GPS and headlamp charging | No stored energy; output falls with cloud or poor tilt |
| Solar power bank with panel on the case | 1 W to 3 W | 5,000 to 20,000 mAh (18.5 to 74 Wh at 3.7 V) | Emergency top-up and promotional kits | Panel is too small to refill the battery in a useful time |
| Panel plus separate battery pack | 10 W to 30 W | 20 to 100 Wh, set by the buyer | Multi-day trips and several devices | Connector, voltage and current limits must match on both parts |
The ranges in the table are typical ranges for each format in general and are not LinkSolar specifications. LinkSolar's custom foldable page covers foldable panels under your brand; confirm availability before specifying a power-bank format. The first format is the simplest to specify because it has no battery to match or document, and the foldable solar charger for hiking guide covers the phone, GPS and headlamp loads it serves.
The second format places a small panel on a battery case. A 2 W panel at an assumed 0.70 system factor and 5 peak sun hours yields 2 x 5 x 0.70 = 7 Wh, less than half of one 15 Wh phone charge, so that panel tops up a battery slowly and cannot recharge it.
The third format splits panel and battery, so the connector, the voltage window and the current limit must match on both sides. A program aimed at 12 V batteries instead of USB devices fits the solar battery chargers range better.
Sizing panel watts to battery capacity: a worked calculation
A panel rating is sized by dividing the battery energy in watt-hours by the peak sun hours and a system factor. A 10,000 mAh bank with 3.7 V cells holds 10 Ah x 3.7 V = 37 Wh, so with 5 peak sun hours and an assumed 0.70 system factor the refill rating is 37 / (5 x 0.70) = 10.6 W.
Peak sun hours are the daily solar energy in kWh per square metre, so 5 peak sun hours means 5 kWh/m2 on the panel plane that day. The 0.70 system factor is an assumption for this example that stands in for cell heating, tilt, cable and conversion losses, and the real value should be measured on the finished unit.
| Panel rating | Daily energy | Full phone charges per day | Days to refill a 37 Wh bank |
|---|---|---|---|
| 5 W | 17.5 Wh | 1.0 | 2.1 |
| 10 W | 35 Wh | 2.0 | 1.1 |
| 20 W | 70 Wh | 4.0 | 0.5 |
| 30 W | 105 Wh | 6.0 | 0.4 |
Phone charges assume a 15 Wh battery and an 85 percent charging efficiency, so charges = daily energy x 0.85 / 15. Both values are examples, and the how to charge a phone with a solar panel guide covers the phone side of the chain.
The 10 W row is the useful anchor, because it nearly refills the 37 Wh bank in one 5 peak sun hour day. A cloudy day with 2 peak sun hours cuts that result to 10 x 2 x 0.70 = 14 Wh, so a specification should state the light level at which the output rating applies.
Order requirements: compatibility and what to confirm
A private label solar charger order needs three matches confirmed in writing: the connector, the voltage and current the device accepts, and the energy the device uses per day.
A 5 V USB output is the baseline for phones, headlamps and handheld GPS units, and any device that asks for a different voltage needs that voltage listed on the specification. The solar charger for outdoor electronics guide helps check a device list against a charger's output.
Price, minimum order quantity and delivery time stay unknown until a supplier quotes them for your exact configuration, so this article gives none. A current request for quotation sets the real figure.
Six steps take a specification to a released order, each with a record the buyer keeps.
- Write a one-page specification with the device list, panel watts, USB output, battery capacity in Wh or none, and branding scope.
- Send the same page to two or three suppliers and compare the quotes line by line against it.
- Approve the artwork proof, including logo position, print method and box layout.
- Test a first unit outdoors and record the output under a stated light level.
- Agree the pre-shipment check items, and ask which records the supplier provides, before the order is released.
- Release the volume order and confirm the export documents with your freight forwarder.
FAQ
What is the difference between private label and OEM solar chargers?
Private label starts from an existing design and applies the buyer's brand, while OEM builds to the buyer's own drawing or specification. Many programs sit between the two, for example an existing panel with a custom cable and new packaging. The quotation should state which parts are fixed and which the buyer controls.
Does a private label solar charger need a built-in battery?
A panel with a USB output charges a device directly while light falls on it, so a built-in battery is optional. A battery stores energy for the evening but adds capacity matching, can add transport paperwork and needs a separate test plan. Ask a freight forwarder and a test lab which documents apply to lithium cells in your destination market.
How many watts does a solar charger need to charge one phone per day?
A 10 W panel delivers about 35 Wh on a day with 5 peak sun hours, which is about two charges of a 15 Wh phone battery. The 0.70 system factor and the 15 Wh battery are assumptions, so recompute with the target phone and the light level you expect. A 5 W panel gives about one charge under the same inputs.
What can carry my brand on a solar charger?
The usual branded items are the logo on the panel face or case, the retail box, the manual and the barcode label. Print method, color and position should be fixed on an artwork proof before production. Ask the supplier which artwork file formats it needs before design starts.
What should a supplier send before I approve production?
Ask the supplier which of these it provides: a drawing with dimensions and connector type, an artwork proof and an output reading taken under a stated light level. Add the pre-shipment check items you want recorded. Keep these documents in the order file for later comparison with the shipped units.
Next step
The next step after this checklist is sending the written requirements, because the power, size, quantity and target market decide which stock panel can carry your brand and what has to be custom.
Prepare those four inputs, and browse the stock solar phone chargers if you want to name a model to mark and pack. LinkSolar is a China-based B2B supplier of custom & OEM solar panels, solar cells and mounting hardware.